Hot-blast stove



(No Model.)

I W. ROTTHOFP. HOT BLAST sTovB.

No. 312,902. en

EL l

2 Sheets--Sheei-J 1,

ted Feb. 24, 1885.`

f f f WITNESSES;

J/Taj INVENTOR, WMM@ @AH/1# BY v//z ATTORN EY.

(No Model.) W ROTTHOPF 2 Sheets-Sheet 2.

HOT BLAST STOVB.

Patented eb. 24, v1885.

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INVENTOR.

WITNESSES:

BY @mt To aZZ whom it may concern:

Nrrrrn grains Paritair @jerica VIJLIAM RQTTHOFF, OF PITTSBURG, PENNSYLVANIA.

MOTU-BLAST' STOVE.

SPECIFECATIOIT forming part of Letters Patent No. 312,902, dated February 2%, 1885.

Application filed October 23, 1884. (No model.)

Be it known that I, WILLIAM Rorrriorr, a subject of the Emperor of Germany, residing` at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented or discovered certain new and useful Improvements in Hot-Blast Stoves, of which improvements the following is a specification.

In the accompanying drawiugs,wliich make part of this specification, Figure 1 is a seetional elevation of my improved hot-blast.

stove. Fig. 2 is apartially top plan and partially sectional plan view, the -sections being taken on` the lines m, y, and e, Fig. 1. Figs. 3 and 4 are detail views of certain partsof the stove.

the necessity of alternating the flow of the heating-gas and the blast, as is necessary in the Vvfhitwell form of stove, this form of stove' `requiring duplicate stoves in order to'produce a continuous hot blast for the furnace; and a further object of niy invention is to avoidthe liability of the bursting of the pipes in that class oi' stoves in which a continuous blast is attained without a duplication of the stoves; and to these ends my invention consists, generally stated, in the construction and combination of parts, all `as more fully hereinafter described and claimed.

Upon suitable pillars, 1, is supported the curved bed-plate 2, having the depending flange 3, to which is secured the casing of the gassupply chamber, having the shape of an inverted cone, said casing being lined with tire-brick orl other refractory material, the lower end of said chamber being normally closed by the conical stopper 5, held in place by the lever 6, pivoted to the side of said chamber, the upper end of said chamber being closed by a tire-brick arch.

In the side of the chamber 4 is formed the opening 7, through which gas is conducted by a suitable pipe from the top of the blast-furnace into the chamber. From thence it passes into burners 8, inserted in openings 9 in the top of the chamber.

On the bed-plate 2 is formed a series of radial partitiouwalls, 10, which in turn support the bottom plate, 11, of the heatingchamber, said plate being formed integral with the main partitions 1() and with the wingwalls 12, projecting from the main partitionwalls, and forming, in connection with the main walls, pockets or chambers 13, opening at their outer ends, as shown in Fig. 1.

In the bed-plate 2 and bottom plate, 11, are formed a series of openings, 14, said openings 'being in line with the openings 9 in the top of the chamber 4, and so arranged that only one opening in each plate shall be located in the same pocket or chamber' 13. Through these openings 14 and through the pockets pass the burners 8, as shown in Fig. 1, the upper end of each burner being provided with a removable tip, 15, said tips being formed tapering so as to iit loosely in the openings 14 in the bottom plate, 1l, and being provided with projecting lugs for the purpose of centering the tips within the openings 14, the burners 8 held in position by lugs 16, projeeting therefrom below the bed-plate, and provided with pins projecting up through holes'in said bed-plate, and held in position by keys passing through slots in that portion of the pins which project above the bed-plate. The open ends of the pockets 13 are closed by doors 17, hinged to the'periphery of the bottom plate, 11, said doors being provided with catches adapted to engage toothed bars 13, projecting from the bed-plate 2, for the purpose of holding the doors in an open or.

closed position.A

The heating-chamber is formed on the bottom plate, 11, the outer casing, 19, oi" said chamber being secured tothe peripheral iiange 20 of the bottom plate.

fire-brick or other refractory material, a slight space being left between the fire-brick wall and the outer casing, said space being filled with asbestos or mineral wool. v

Through the heating-chamber are passed a series of pipes, 21, the lower ends of said pipes resting upon the bottom plate, 11, within anges 22, formed around the openings 14 in said plate, through which the tips 15 of the burners project, as above stated, the space between the lower ends of the pipes 21 and the The inner walls and 9o bottom of the heating-chamber are formed of.

I 1o packing is forced down between the boxes and pipes by the glands 25, fitting closely around the pipes and within the boxes, said glands being connected to the boxes by the threaded bolts 26, on which are placed the springs 27,

r said springs being arranged between the top of the gland and the nut on the bolt, so as to allow of the yielding of the packing and gland on the longitudinal lexpansion ofthe pipes 21.

Over the center of the heatingchamber is 2o formed a man-hole, 28, to allow access to said chamber.

Diametrically across the chamber`is formed the wall29, extending from the bottom nearly to the top and dividing said chamber into two compartments, into one of which the cold blast is conducted by the branch pipes 30, extending from the main conductor 31, and entering the heating-chamber near the bottom. The hot-blast pipe 32 leading to the tuyeres is inserted into the other compartment near the bottom plate.

It will be observed that the pipes 21 are arranged in sets of three, and for each set I provide a peep-hole, 33, through the wall of the heating-chamber, said peep-hole being so located with reference to the pipes of a set that each pipe of the set can be inspected through a glass plate secured over the mouth of said holes.

To the top of each of the pipes 21 is secured the bracket 34, to which is pivoted the arm of the damper 35, the outer end of said arm being provided with a rod or chain, whereby said damper may be operated.

In Fig. 4, I have shown the manner of connecting two lengths of pipe in case it is desirable to form the pipes 21 in sections. Near the ends of one of the sections is formed the. ange 36, on which rests the band 37, surrounding the sections at their abutting ends, the space between the band and the sections being packed with iron filings or other suitable material.

I provide for the easy removal of the glands 5 5 2 5 by forming curved slots 38in the fianges of the stuffing boxes for the reception of the bolts 26. In order to remove the glands, itis only necessary to loosen the nuts on the bolts and give a partial turn to the glands, when 6o the bolts will be freed from the slots in the iiange of the stuffing-box.

At times it may be desirable to dispense with the use of gas from the blast-furnace, in which case I provide for the generation of 4gas in the supply-chamber by placing grate-bars 39 in the gas-supply chamber 4, the fuel being charged upon said grate-bars through the opening 40, formed in the walls of the chamber, the draft being regulated by the opening and closing of the stopper 5, the gases being conducted, as before described, into the pipes 21 by the burners 8. t

In using this stove the gas is conducted from the blast-furnace through the opening 7 into the supply-chamber, the opening 40 and that in the bottom of the chamber 4 being closed, or else generated therein, as above stated. From thence it passes through the burners 8 into the pipes 21, where, mingling with air entering the pipes around the tips 15, it is burned, highly heating said pipes. The blast is forced into the lower part of one of the compartments, from whence, after circulating around the pipes in said compartment, it passes up over the partition-wall 29, and then passes down and around the pipes in the other com partment, out through the hot blast-pipe 32 to the tuyeres. By opening and closing the doors 17 of the pockets 13 the amount ofair supplied to each of the burners can be regulated, and as there is only one burner in each pocket, each burner can be independently regulated, and, if necessary, the combustion in any of the burners can be stopped or reduced by closing or partially closing the damper at the top of pipe 21 and the door of the pockets.

The glands 25 should not be forced down tightly on the packing until after the expansion caused by heating the pipes 21 has taken place. In case of the burning out or any other injury toany of the pipes,said injured pipe can be removed and another inserted in its place by removing the gland,when the exchange can be easily effected.

If desired, valves may be placed in the burners 8 for the purpose of regulating and cutting oft the gas from any one of the pipes.

It will be observed that as the blast passes around the pipes instead of through them, as in some forms of stoves, there is no danger of destroying said pipes by the high pressure of the blast, and as the air is heated by passing along surfaces which can be constantly heated, I avoid the duplication of part-s necessary in that class of stoves in which the heating agent and the air are passed alternately over the same surfaces.

In lieu of the doors 17 the mouth of the pockets 13 may be closed, or partially so', by placing bricks therein, or any other convenient means for effecting the regulation ofthe aperture of the pockets may be adopted.

The dividing-wall 29 may, if desired, be

omitted, in which case the cold blast should enter the heating-chamber near the top, and

the heated blast escape from an opening near f the bottom on the opposite side of the chamber, and in some cases it may be desirable to employ two yor more dividing-walls in the heating-chamber, so as to insure a more thorough circulation and consequent heating of the blast.

I claim herein as my invention* 1. In a hot-blast stove, a heating-chamber,

IOO

IIO

having a Wall passing transversely across said chamber7 in combination with a series of openended pipes passing through the chamber7 said pipes being separated from each other, so as to allow of a free circulation of the air around each, and a like series of gasfburners having their tips Within the ends of the pipes, substantially as set forth.

2. In a hot-blast stove, the combination of a heating-charnber, having a series of openended pipes passing therethrough, and a like series of gas-burners located in line with said pipes, each of said burners passing through separate pockets or chambers in the base of the heatingeh anlber, substantially as set forth.

3. In a hot-blaststove, the combination of a heating-chamber, a series of pockets formed on the under side of the bottoni plate of the heatingcharnber, and a series of gas-burners passing through saidpookets, and projecting through openings in the bottom plate ot' the heating-chamber, substantially as set forth.

4. In a hot-blast stove7 a heating-chamber, having a base provided with series of openended pockets, in combination with a series of gas-burners passing through the pockets, i

and a series of doors for regulating the admission of air to said pockets, substantially as set forth.

5. In a hot-blast stove, a gas-supply chamber, in combination with au air-heating charnber, having a series of openended pipes passing therethrough, and a series of burners for .conducting the gas from the supplychamber into the pipes in the heating-chamber, substantially as set forth.

6. In a hot-blast stove, aheatingchamber, having a base provided With a series of openended pockets7 in combination with a series of gas burners passing through' the pockets, means for obstructing or elosing the open ends of the pockets, a series ofpipes passing through the heating-chamber and arranged with their axes in line with the axes of the gas-burners, and dampers located at the top ot' said pipes, substantially as set forth.

In testimony whereof I have hereunto set my hand.

IVILLIAM ROT'IHOFF.

Witnesses:

DARWIN S. WoLoorT, RII. WI-IIT'rLnsEY. 

